From: Amitay Isaacs <amitay@gmail.com>
Date: Tue, 15 Jul 2014 04:13:25 +0000 (+1000)
Subject: ctdb-locking: Add DB lock requests to head of the pending queue
X-Git-Url: http://git.samba.org/?a=commitdiff_plain;h=7189437be447d33038eb26bca055b1025cebacd3;p=obnox%2Fsamba%2Fsamba-obnox.git

ctdb-locking: Add DB lock requests to head of the pending queue

This allows to schedule DB locks quickly without having to scan through
the pending lock requests.

Signed-off-by: Amitay Isaacs <amitay@gmail.com>
Reviewed-by: Volker Lendecke <vl@samba.org>
---

diff --git a/ctdb/server/ctdb_lock.c b/ctdb/server/ctdb_lock.c
index b9740857c1d..1100c7c17ab 100644
--- a/ctdb/server/ctdb_lock.c
+++ b/ctdb/server/ctdb_lock.c
@@ -858,7 +858,14 @@ static struct lock_request *ctdb_lock_internal(struct ctdb_context *ctdb,
 	lock_ctx->request = request;
 	lock_ctx->child = -1;
 
-	DLIST_ADD_END(ctdb->lock_pending, lock_ctx, NULL);
+	/* Non-record locks are required by recovery and should be scheduled
+	 * immediately, so keep them at the head of the pending queue.
+	 */
+	if (lock_ctx->type == LOCK_RECORD) {
+		DLIST_ADD_END(ctdb->lock_pending, lock_ctx, NULL);
+	} else {
+		DLIST_ADD(ctdb->lock_pending, lock_ctx);
+	}
 	CTDB_INCREMENT_STAT(ctdb, locks.num_pending);
 	if (ctdb_db) {
 		CTDB_INCREMENT_DB_STAT(ctdb_db, locks.num_pending);